Abstract
Hume is generally thought to hold that spatial contiguity is essential to the causal relation. Indeed, Pears, in his recent "Hume's System", adds to Hume's system the claim that perceptions must exist somewhere--have, that is, spatial coordinates--so that, he claims, we can identify them as well as solve the problem of sorting out one person's perceptions from another. Pears fails to accomplish his aims in this attempt, but, more seriously, he fails to understand Hume's commitment to some perceptions being the sorts of things that do not have spatial coordinates. He thus fails to understand that Hume is attempting to displace a conception of causal relations which makes it impossible to have a unified theory of causation for everything that exists in the world. But Hume does not hold that all perceptions have spatial coordinates, and since he does hold that anything can be the cause of anything else, he holds that some causal relata are not spatially located. My willing to raise my arm is an instance of such a causal relation for Hume